# Constraining Relativistic Generalizations of Modified Newtonian Dynamics with Gravitational Waves

## TL;DR

This paper examines relativistic modifications of Modified Newtonian Dynamics, showing that two prominent theories are incompatible with gravitational wave observations and cosmic ray data, challenging their viability.

## Contribution

It critically analyzes two relativistic MOND theories, revealing their inconsistencies with recent gravitational wave and cosmic ray observations.

## Key findings

- Generalized Einstein-Aether theory conflicts with gravitational wave speed observations.
- BIMOND theory shows inconsistencies with ultra high energy cosmic ray data.
- Both theories are challenged as viable alternatives to dark matter.

## Abstract

In the weak-field limit of General Relativity, gravitational waves obey linear equations and propagate at the speed of light. These properties of General Relativity are supported by the observation of ultra high energy cosmic rays as well as by LIGO's recent detection of gravitation waves. We argue that two existing relativistic generalizations of Modified Newtonian Dynamics, namely Generalized Einstein-Aether theory and BIMOND, display fatal inconsistencies with these observations.